#include <stdio.h>

typedef struct {
    int width;
    int length;
} rect_t;

int rect_area(rect_t* rect) {
    return rect->width * rect->length;
}

int main(int argc, char** argv) {
    rect_t r;
    r.width = 10;
    r.length = 25;
    int area = rect_area(&r);
    printf("Area: %d\n", area);
    
    return 0;
}